Substantial governmental relationship
Substantial governmental relationship means the extent of a governmental relationship necessary under applicable state law to make an added guarantee contract issued incident to that relationship valid and enforceable. A guarantee contract is issued incident to that relationship if it arises from a clear commonality of interest in the event of an UST release such as coterminous boundaries, overlapping constituencies, common groundwater aquifer, or other relationship other than monetary compensation that provides a motivation for the guarantor to provide a guarantee.
Source
40 CFR § 280.92
Scoping language
When used in this subpart, the following terms shall have the meanings given below: